Suture anchor with pulley

ABSTRACT

Methods and devices are provided for anchoring suture to bone. In one exemplary embodiment, a cannulated suture anchor is provided and it includes a suture-engaging member formed therein and configured to receive a suture therearound such that trailing ends of the suture can extend through the suture anchor. The present invention also provides exemplary sutures and drivers that can be used with the various methods and devices disclosed herein, or with other methods and devices known in the art.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a divisional of U.S. patent application Ser.No. 11/555,557, filed on Nov. 1, 2006, and entitled “SUTURE ANCHOR WITHPULLEY,” which is hereby incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

The complete or partial detachment of ligaments, tendons and/or othersoft tissues from their associated bones within the body are relativelycommonplace injuries, particularly among athletes. Such injuries aregenerally the result of excessive stresses being placed on thesetissues. By way of example, tissue detachment may occur as the result ofan accident such as a fall, over-exertion during a work-relatedactivity, during the course of an athletic event, or in any one of manyother situations and/or activities.

In the case of a partial detachment, the injury will frequently healitself, if given sufficient time and if care is taken not to expose theinjury to further undue stress. In the case of complete detachment,however, surgery may be needed to re-attach the soft tissue to itsassociated bone or bones. Numerous devices are currently available tore-attach soft tissue to bone. Examples of such currently-availabledevices include screws, staples, suture anchors and tacks. In softtissue re-attachment procedures utilizing screws, the detached softtissue is typically moved back into its original position over the bone.Then the screw is screwed through the soft tissue and into the bone,with the shank and head of the screw holding the soft tissue to thebone. Similarly, in soft tissue re-attachment procedures utilizingstaples, the detached soft tissue is typically moved back into itsoriginal position over the bone. Then the staple is driven through thesoft tissue and into the bone, with the legs and bridge of the stapleholding the soft tissue to the bone.

In soft tissue re-attachment procedures utilizing suture anchors, ananchor-receiving hole is generally first drilled in the bone at thedesired point of tissue re-attachment. Then a suture anchor is deployedin the hole using an appropriate installation tool. This effectivelylocks the suture to the bone, with the free end(s) of the sutureextending out of the bone. The free ends of the suture are passedthrough or around the soft tissue and are used to tie the soft tissuesecurely to the bone.

While current suture anchors are effective in anchoring soft tissue tobone, one drawback with current devices is that the suture anchor musthave a head with a length that is sufficient to withstand a torqueapplied thereto by a driver. As a result of the increased length, thesuture anchor will typically extend at least partially into underlyingsoft cancellous bone in order to position the head beneath the outersurface of the bone. The bone-engaging portion of the suture anchor willthus be mostly disposed within and engaged with cancellous bone, ratherthan cortical bone. This is due to the fact that the cortical bone isonly about 1 mm to 3 mm in length, and the driver head is often longerthan 3 mm. Once implanted, tension applied to the anchor via the suturescan cause the anchor to migrate into the cortical bone and thus the headof the suture anchor can become proud, resulting in a weak fixationamong other problems.

Accordingly, there remains a need for improved methods and devices forattaching soft tissue to bone.

SUMMARY OF THE INVENTION

In one embodiment, a suture anchor is provided having an elongate bodywith proximal and distal ends and an inner lumen extending therethrough.At least one bone-engaging surface feature, such as a thread, can beformed on at least a portion of an external surface thereof for engagingbone. The inner lumen of the elongate body can include a suture-engagingmember extending substantially transverse to an axis of the inner lumenand adapted to receive a suture therearound such that a suture canextend around the suture-engaging member and trailing ends of the suturecan extend through the inner lumen and out of the proximal end of theelongated body.

The elongate body can have a variety of configurations. In oneembodiment, the elongate body can include cut-outs formed in opposedsidewalls thereof and extending proximally from the distal end of theelongate body. The cut-outs can be in communication with the innerlumen. In an exemplary embodiment, the suture-engaging member ispositioned distal of a proximal end of the cut-outs. The suture-engagingmember can be, for example, a post extending between opposed walls ofthe inner lumen. In another embodiment, the suture-engaging member canbe positioned just proximal to a distal-most end of the elongated bodysuch that the distal end of the elongated body includes a suture-seatinggroove formed therein and configured to seat at least one suture. Theelongate body can also include other features. For example, at least aportion of the inner lumen can have an asymmetrical cross-sectionalshape, such as a hexagonal cross-sectional shape, for receiving a drivertool therein. In another embodiment, the distal end of the elongate bodycan be rounded.

In another embodiment, a suture anchor is provided having a threaded,cannulated body with proximal and distal ends. The distal end caninclude opposed cut-outs formed in opposed sidewalls thereof and asuture-engaging member extending between the opposed sidewalls andadjacent to the opposed cut-outs such that a suture can extend aroundthe suture-engaging member and trailing ends of the suture can extendthrough the body. In an exemplary embodiment, the suture-engaging memberextends substantially perpendicular to a longitudinal axis of the body.The device can also include a suture disposed around the suture-engagingmember and having trailing ends extending through the body.

In yet another embodiment, an apparatus for anchoring tissue to bone isprovided and includes a suture anchor having an inner lumen extendingbetween proximal and distal ends thereof. The distal end can includeopposed cut-outs formed in opposed sidewalls thereof and asuture-engaging member extending between the opposed sidewalls andadjacent to the opposed cut-outs such that a suture can extend aroundthe suture-engaging member and trailing ends of the suture can extendthrough the inner lumen of the suture anchor. The apparatus can alsoinclude a driver having an elongate shaft and a distal end adapted to bereceived within and to engage a proximal portion of the inner lumen ofthe suture anchor. In an exemplary embodiment, the elongate shaftincludes an inner lumen extending therethrough for receiving a sutureextending through the inner lumen of the suture anchor. A distal end ofthe elongate shaft can include opposed cut-outs formed therein forallowing a suture extending from the suture anchor to extend externallyalong the elongate shaft of the driver. In other embodiments, the distalend of the elongate shaft can include a hexagonal cross-sectional shape,and at least a proximal portion of the inner lumen the suture anchor canhave a complementary hexagonal cross-sectional shape.

Methods for anchoring suture to bone are also provided. In one exemplaryembodiment, the method can include coupling a suture to a suture anchorsuch that the suture extends around a suture-engaging member formed in adistal end of the suture anchor and trailing ends of the suture extendthrough an inner lumen extending through the suture anchor. A driver canbe inserted into the proximal end of the suture anchor, and the trailingends of the suture anchor can extend through an inner lumen formed inthe driver. The driver can then be actuated to insert the suture anchorinto bone to anchor the suture to the bone. While the suture can havevarious configurations, in one embodiment the suture can include firstand second suture strands that extend around the suture-engaging memberand that have trailing ends that extend through the inner lumen of thesuture anchor and through the inner lumen of the driver. In otherapsects, the suture anchor can include threads formed thereon and thedriver can be rotated to drive the suture anchor into bone. In anexemplary embodiment, the threads extend from a proximal end of thesuture anchor to a distal end of the suture anchor such that the sutureanchor is fully threaded into bone.

In yet another embodiment, a suture anchor is provided having anelongate body with proximal and distal ends and an inner lumen extendingtherethrough. At least one bone-engaging surface feature can be formedon an external surface thereof for engaging bone. The suture anchor canalso include a rotatable member extending between opposed sidewalls ofthe inner lumen and adapted to rotate relative to the elongate body. Inone embodiment, the rotatable member can be disposed adjacent the distalend of the elongate body, and it can extend substantially perpendicularto a longitudinal axis of the suture anchor. The rotatable member canbe, for example, a post extending between opposed walls of the innerlumen. In another embodiment, the elongate body can include cut-outsformed in opposed sidewalls thereof, extending proximally from thedistal end of the elongate body, and in communication with the innerlumen. The rotatable member can be positioned distal of a proximal endof the cut-outs. In another embodiment, the rotatable member can bepositioned just proximal to a distal-most end of the elongated body suchthat the distal end of the elongated body includes a suture-seatinggroove formed therein and configured to seat at least one suture. Thedevice can also include a suture disposed around the rotatable memberand having trailing ends extending through the suture anchor.

In other aspects, an apparatus for anchoring tissue to bone is providedand includes a suture anchor having at least one surface feature formedon an external surface thereof and adapted to engage bone, an innerlumen extending therethrough between proximal and distal ends thereof,and a rotatable member extending across opposed sidewalls of the innerlumen such that a suture can extend around the rotatable member andtrailing ends of the suture can extend through the inner lumen of thesuture anchor. The apparatus can also include a driver having anelongate shaft and a distal end adapted to be received within and toengage a proximal portion of the inner lumen of the suture anchor.

Exemplary methods for anchoring suture to bone are also provided, and inone embodiment the method can include coupling a suture to a sutureanchor such that the suture extends around a rotatable member rotatablydisposed within in a distal end of the suture anchor and trailing endsof the suture extend through an inner lumen extending through the sutureanchor. A driver can be inserted into the proximal end of the sutureanchor, and the driver can be actuated to insert the suture anchor intobone and thereby anchor the suture to the bone. The method can alsoinclude pulling one of the trailing ends of the suture to cause therotatable member to rotate. In one embodiment, the driver can be removedfrom the suture anchor prior to pulling one of the trailing end of thesuture. In an exemplary embodiment, the suture can include a wireattached thereto and pulling the suture can include pulling the wire. Inother embodiments, a second suture can be coupled to the wire such thatpulling the wire pulls both sutures around the rotatable member andthrough the inner lumen of the suture anchor.

In yet another embodiment, a suture anchoring system is provided andincludes a suture anchor having an inner lumen extending therethroughand a suture-engaging member extending across opposed sidewalls of theinner lumen, and at least one suture having a terminal end that iscoupled to at least one wire extending through the inner lumen of thesuture anchor and around the suture-engaging member. In an exemplaryembodiment, the wire(s) has a diameter that is less than a diameter ofthe suture(s) coupled thereto. The wire(s) can be connected to thesuture(s) using various techniques, such as threading the wire(s)through the terminal end of the suture(s), looping the wire(s) aroundthe terminal end of the suture(s), welding the wire(s) to the terminalend of the suture(s), mating the wire to the terminal end of the atleast one suture using a crimp band, and winding a coiled portion of thewire(s) around the terminal end of the suture(s). The suture anchoringsystem can also include a driver having a distal end adapted to extendinto and engage the inner lumen of the suture anchor. The wire(s) caninclude a first terminal end coupled to the terminal end of thesutures(s), and a second terminal end coupled to the driver.

In yet another embodiment, a suture anchoring system is provided havinga threaded, cannulated suture anchor with proximal and distal ends, anda suture-engaging member disposed within a distal end of the sutureanchor, and at least one suture having a terminal end that is coupled toa wire extending through the suture anchor and extending around thesuture-engaging member. The system can also include a driver having adistal end adapted to extend into and engage the a proximal end of thesuture anchor.

In other aspects, a method for anchoring suture to bone is provided andincludes coupling a wire to a suture anchor such that the wire extendsaround a suture-engaging member extending across opposed sidewalls of aninner lumen of the suture anchor and first and second terminal ends ofthe wire extend through the inner lumen of the suture anchor, insertingthe suture anchor into bone, and pulling the first terminal end of thewire to pull at least one suture strand coupled to the second terminalend of the wire through the inner lumen of the suture anchor and aroundthe suture-engaging member. In one embodiment, the wire can be coupledto first and second suture strands such that pulling the first terminalend of the wire pulls the first and second suture strands through theinner lumen of the suture anchor and around the suture-engaging member.Alternatively, the wire can be coupled to a driver that is inserted intothe inner lumen of the suture anchor, and that is actuated to drive thesuture anchor into bone. Removing the driver from the suture anchor canbe effective to pull the wires. The method can also include injecting amaterial through the inner lumen of the driver and into the inner lumenof the suture anchor. The material can be, for example, a bone-growthpromoting material, a sealant, an adhesive, and combinations thereof.The method can also include attaching the suture(s) to tissue to anchorthe tissue to the bone.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be more fully understood from the following detaileddescription taken in conjunction with the accompanying drawings, inwhich:

FIG. 1A is a perspective view of one embodiment of a cannulated sutureanchor;

FIG. 1B is a cross-sectional view of the suture anchor of FIG. 1A;

FIG. 1C is a perspective view of the suture anchor of FIG. 1A havingfirst and second sutures coupled thereto;

FIG. 2 is a cross-sectional view of a distal portion of a suture anchorhaving a rotatable suture-engaging member according to anotherembodiment of the present invention;

FIG. 3A is a cross-sectional view of one embodiment of a driver tool;

FIG. 3B is a perspective view of the driver tool of FIG. 3A;

FIG. 3C is a perspective view of the driver tool of FIG. 3A coupled to asuture anchor and having a suture extending therethrough;

FIG. 4A is a cross-sectional view of the suture anchor of FIG. 1A havinganother embodiment of a driver tool disposed therein;

FIG. 4B is a cross-sectional view of the driver tool of FIG. 4A takenacross line B-B;

FIG. 5A is a perspective view of the suture anchor of FIG. 1A havingfirst and second sutures coupled thereto, showing a wire coupled to theterminal end of each suture;

FIG. 5B is a perspective view of the suture anchor of FIG. 1A havingfirst and second sutures coupled thereto, showing first and second wirescoupled to the terminal ends of the first and second sutures,respectively;

FIG. 5C is a perspective view of the suture anchor and sutures of FIG.5B, showing the wires pulling the sutures through the suture anchor;

FIG. 6 is a side view of a technique for threading a wire to a suture;

FIG. 7 is a side view of a technique for tying a wire to a suture;

FIG. 8 is a side view of a technique for welding a wire to a suture;

FIG. 9 is a side view of a technique for mating a wire to a suture usinga clamp;

FIG. 10 is a side view of a technique for mating a wire to a sutureusing a coil formed on the wire;

FIG. 11A is a cross-sectional view of the suture anchor of FIG. 1Ahaving a wire extending therethrough and coupled to a distal end of adriver;

FIG. 11B is a cross-sectional view of the suture anchor of FIG. 1Ahaving a wire extending therethrough and coupled to a proximal end of adriver;

FIG. 11C is a cross-sectional view of a portion of a driver tool,showing a technique for mating a wire thereto;

FIG. 12A is a cross-sectional view of the suture anchor of FIG. 1A,showing one technique for coupling two sutures thereto;

FIG. 12B is a cross-sectional view of the suture anchor of FIG. 1A,showing another technique for coupling two sutures thereto;

FIG. 12A is a cross-sectional view of the suture anchor of FIG. 1A,showing a technique for coupling a suture thereto; and

FIG. 12A is a cross-sectional view of the suture anchor of FIG. 1A,showing yet another technique for coupling a suture thereto.

DETAILED DESCRIPTION OF THE INVENTION

Certain exemplary embodiments will now be described to provide anoverall understanding of the principles of the structure, function,manufacture, and use of the devices and methods disclosed herein. One ormore examples of these embodiments are illustrated in the accompanyingdrawings. Those of ordinary skill in the art will understand that thedevices and methods specifically described herein and illustrated in theaccompanying drawings are non-limiting exemplary embodiments and thatthe scope of the present invention is defined solely by the claims. Thefeatures illustrated or described in connection with one exemplaryembodiment may be combined with the features of other embodiments. Suchmodifications and variations are intended to be included within thescope of the present invention.

The present invention generally provides methods and devices foranchoring suture to bone. In an exemplary embodiment, a cannulatedsuture anchor is provided and it includes a suture-engaging memberformed therein and configured to receive a suture therearound such thattrailing ends of the suture can extend through the suture anchor. Theuse of a cannulated suture anchor also allows a driver to be insertedinto the inner lumen of the suture anchor for driving the suture anchorinto bone. Such a configuration will allow the torque strength of thesuture anchor to be maximized due to the increased engagement betweenthe suture anchor and the driver. This in turn will allow the sutureanchor to be formed from a broad range of materials, includingbioabsorbable and/or osteoconductive materials. The use of a cannulatedsuture anchor will also eliminate the need for a driver head formed onthe suture anchor, and as a result the entire length of the sutureanchor can be configured to be fully engaged through the thickness ofhard cortical bone, thus optimizing cortical bone fixation to provide amore secure fixation. This will help prevent migration of the sutureanchor. A cannulated suture anchor is also particularly advantageous asit allows materials, such as bone-growth promoting materials, sealants,adhesives, etc., to be introduced therein to facilitate fixation. Thepresent invention also provides exemplary sutures and drivers that canbe used with the various methods and devices disclosed herein, or withother methods and devices known in the art. A person skilled in the artwill appreciate that, while methods and devices are disclosed herein foranchoring soft tissue to bone, the methods and devices can be used in avariety of other medical procedures for anchoring various objects to oneanother.

FIGS. 1A-1C illustrate one exemplary embodiment of a cannulated sutureanchor 10 for anchoring soft tissue to bone. As shown, the suture anchor10 is in the form of a generally elongate body having proximal anddistal ends 10 a, 10 b with an inner lumen 10 c extending therethrough.At least one bone-engaging surface feature 12 can be formed on at leasta portion of an external surface thereof for engaging bone. The sutureanchor 10 also includes a suture-engaging member 14 disposed within theinner lumen 10 c adjacent to the distal end 10 b of the suture anchor10. As shown in FIG. 1C, the suture-engaging member 14 is adapted toreceive one or more sutures (two sutures 16, 18 are shown) therearoundsuch that the suture(s) can extend around the suture-engaging member 14and trailing ends of the suture(s) can extend through the inner lumen 10c and out of the proximal end 10 a of the suture anchor 10.

The body of the suture anchor 10 can have a variety of configurations,shapes, and sizes. In an exemplary embodiment, the body is configured tobe implanted within a bone tunnel formed in bone, and more preferably ithas a size and shape that allows it to be fully engaged through thethickness of the cortical bone. In the illustrated embodiment the bodyhas a generally elongate cylindrical shape with a blunt or roundeddistal end 10 b to facilitate introduction into a bone tunnel. Theproximal end 10 a of the body is head-free, as the cannulatedconfiguration of the body allows a driver to be inserted into the innerlumen 10 c to drive the suture anchor 10 into bone. As indicated above,the suture anchor 10 can also include one or more bone-engaging surfacefeatures formed thereon and adapted to engage bone. While varioussurface features can be used, such as teeth, ridges, protrusions, etc.,in an exemplary embodiment the body can include one or more threadsextending therearound. In the illustrated embodiment a single threadextends around the body from the proximal end 10 a and it terminatesproximal to the distal end 10 b. The particular location at which thethread terminates can vary depending on the particular configuration ofthe suture anchor 10. As will be discussed in more detail below, theillustrated suture anchor 10 can include opposed cut-outs formed in thedistal end thereof and the thread can terminate just proximal to theproximal end of the cut-outs.

The suture anchor 10 can also be formed from a variety of materials. Inan exemplary embodiment, the material has physical properties that aresufficient to allow a driver to be inserted into the inner lumen 10 c ofthe suture anchor 10 and to be used to drive the suture anchor 10 intobone without damaging the suture anchor 10. The properties of thematerial will of course depend on the particular configuration of thesuture anchor 10. For example, the inner lumen 10 c of the suture anchor10 can have a length that maximizes the torque strength of the sutureanchor 10 as well as the amount of surface contact between a driver andthe suture anchor 10, thus allowing weaker materials, such asbioabsorbable and/or osteoconductive materials to be used. A personskilled in the art will appreciate that a variety of other materials,including plastics and metals, can be used to form the suture anchor 10.

As previously indicated above, the suture anchor 10 can also include asuture-engaging member 14 formed therein. The suture-engaging member 14can have a variety of configurations, but in an exemplary embodiment itis adapted to engage one or more sutures that extend through the innerlumen 10 c of the suture anchor 10. As shown in FIGS. 1A and 1B, thesuture-engaging member 14 is in the form of a post that extendstransversely across the inner lumen 10 c and between opposed innersidewalls of the suture anchor 10. The angular orientation of thesuture-engaging member 14 relative to a longitudinal axis A of the innerlumen 10 c can vary, but in an exemplary embodiment the suture-engagingmember 14 extends substantially perpendicular to the longitudinal axis Aof the inner lumen 10 c. The location of the suture-engaging member 14can also vary, but in an exemplary embodiment the suture-engaging member14 is positioned at or adjacent to the distal end 10 b of the sutureanchor 10. In the embodiment shown in FIGS. 1A and 1B, thesuture-engaging member 14 is located just proximal to the distal-mostend 10 b of the suture anchor 10 so as to form a suture-seating groove22 a in the distal-most end of the suture anchor 10. This recessedconfiguration of the suture-engaging member 14 can allow a suture(s)disposed around the suture-engaging member 14 to sit flush or sub-flushwith the distal end 10 b of the suture anchor 10 such that the suture(s)will not interfere with insertion of the suture anchor 10 into bone. Aperson skilled in the art will appreciate that the suture-engagingmember 14 can be integrally formed with the suture anchor 10, i.e., thesuture anchor 10 and suture-engaging member 14 can be molded as a singleunit or formed from a single piece of material, or the suture-engagingmember 14 can be fixedly or removably mated to the suture anchor 10.

As further shown in FIGS. 1A-1C, in order to facilitate positioning of asuture(s) around the suture-engaging member 14, the suture anchor 10 caninclude one or more cut-outs formed in a sidewall thereof adjacent tothe suture-engaging member 14. As best shown in FIG. 1A, in an exemplaryembodiment the suture anchor 10 includes a cut-out 22 that begins justproximal to the location of the suture-engaging member 14, and thatextends around the distal end 10 b of the suture anchor 10 such that thesuture anchor 10 includes opposed cut-outs or openings formed on opposedsides of the suture-engaging member 14 and a distal cut-out that definesthe suture-seating groove 22 a for seating a suture(s). The cut-out 22can also define opposed distal arms 11 a, 11 b on the suture anchor 10that are spaced a distance apart from one another and that have thesuture-engaging member 14 extending therebetween.

A person skilled in the art will appreciate that the particular locationand configuration of the cut-out 22 can define the particular locationand configuration of the suture-engaging member 14, as the cut-out 22can be formed during manufacturing to create the suture-engaging member14. Alternatively, the particular location and configuration of theopposed arms 11 a, 11 b can define the particular location andconfiguration of the cut-out 22, as the shape and size of the arms 11 a,11 b defines the shape and size of the cut-out 22. The location of thesuture-engaging member 14 relative to the cut-out 22 and/or arms 11 a,11 b will also define the configuration of the distal end of the sutureanchor 10, and whether the suture anchor 10 includes a distal groove 22a for seating a suture(s).

As further shown in FIGS. 1A and 1B, the inner lumen 10 c of the sutureanchor 10 can be adapted to receive a driver therein for driving thesuture anchor 10 into bone. While various techniques can be used tofacilitate engagement between the inner lumen 10 c and a drivermechanism, in an exemplary embodiment the inner lumen 10 c, or at leasta portion thereof, has an asymmetrical shape that complements acorresponding asymmetrical shape of a driver. The asymmetrical portionpreferably extends along a substantial length of the inner lumen 10 c soas to maximum surface contact between a driver and the suture anchor. Byway of non-limiting example, FIGS. 1A and 1B illustrate a hexagonalcross-sectional shape formed in a proximal portion of the inner lumen 10c for receiving a driver having a corresponding hexagonal drive tip, aswill be discussed in more detail below. The hexagonal cross-sectionextends from the proximal-most end 10 a of the suture anchor 10 andterminates just proximal to the proximal end of the cut-out 22.

In another embodiment, rather than having a fixed suture-engaging member14, the suture anchor can include a suture-engaging member that isrotatably disposed therein. Such a configuration will allow for sutureslidability, providing a pulley system to facilitate longitudinalmovement of a suture through the inner lumen of the suture anchor. Inparticular, one or more terminal ends of one or more sutures disposedaround the suture-engaging member can be pulled to slide the suture(s)longitudinally within the inner lumen of the suture anchor, and thesuture-engaging member can rotate to facilitate such longitudinalmovement.

While the rotatable suture-engaging member can have a variety ofconfigurations, FIG. 2 illustrates one exemplary embodiment of arotatable suture-engaging member 14′ that is disposed within an innerlumen 10 c′ of a suture anchor 10′. As shown, the suture-engaging member14′ is in the form of a generally cylindrical body having opposedsidewalls 15 a′, 15 b′ and a continuously curved outer wall 15 c′extending therearound and between the opposed sidewalls 15 a′, 15 b′. Agroove 15 d′ is formed in the outer wall 15 c′ for seating one or moresutures, such as suture 16′. The suture-engaging member 14′ alsoincludes a bore 15 e′ extending therethrough between the opposedsidewalls 15 a′, 15 b′ for receiving a pin member 20′ that allows thesuture-engaging member 14′ to rotate therearound. The pin member 20′ canextend into opposed bores or openings 9 a′, 9 b′ formed in an innersurface of the opposed arms 11 a′, 11 b′ of the suture anchor 10. Aperson skilled in the art will appreciate that a variety of othertechniques can be used to rotatably mate the suture-engaging member 14′to the suture anchor 10′. Alternatively, other techniques can be used tofacilitate suture slidability, such as a lubricious coating applied tothe suture engaging member.

As previously indicated, the suture anchors disclosed herein can becannulated for receiving a driver. While various drivers known in theart can be used, FIGS. 3A and 3B illustrate one exemplary embodiment ofa driver 30 for driving a suture anchor into bone. In this embodiment,the driver 30 is adapted to allow the terminal ends of a suture(s)extending through the suture anchor to extend along an external surfacethereof. As shown, the driver 30 is in the form of a generally elongateshaft having proximal and distal ends 30 a, 30 b. While not shown, theproximal end 30 a can include a handle or other grasping mechanismformed thereon to facilitate grasping and manipulation of the device.The distal end 30 b includes a reduced diameter portion or tip 32 thatis configured to fit within the inner lumen of a suture anchor, such aslumen 10 c of anchor 10. The shape of the tip 32 can vary, but in anexemplary embodiment it has an asymmetrical shape that allows the tip 32to engage the inner lumen 10 c of the anchor 10. In the illustratedembodiment the tip 32 has a generally hexagonal cross-sectional shapethat complements the generally hexagonal cross-sectional shape of theinner lumen 10 c in the anchor. The length of the tip 32 can also vary,but in an exemplary embodiment the tip 32 has a length that allows it toextend through a substantial portion of the lumen 10 c in the anchor 10so as to maximize surface contact between the tip 32 and the anchor 10.For example, the length 32 can correspond to a length of the hexagonalportion of the inner lumen 10 c in the anchor. A person skilled in theart will appreciate that the tip 32 can have a variety of other shapes,sizes, and configurations.

As further shown in FIGS. 3A and 3B, the tip can also include one ormore suture-receiving recesses or grooves formed therein and extendinglongitudinally along the length of the tip 32 for seating one or moresutures. In the illustrated embodiment first and second opposedsuture-receiving grooves 34 a, 34 b are formed in the tip 32 and extendalong the length thereof. The grooves 34 a, 34 b can also optionallyextend a distance beyond a proximal end of the tip 32, as shown, oralong the entire length of the driver 30, so as to further prevent thesuture(s) from interfering with insertion of the suture anchor 10.

FIG. 3C illustrates a cut-away view of the driver 30 disposed within asuture anchor 100 that is similar to suture anchor 10. As shown, asuture 36 is disposed through the lumen 100 c of the suture anchor 100and around the suture-engaging member 114 such that first and secondtrailing ends 36 a, 36 b of the suture 36 extend proximally from theproximal end 100 a of the suture anchor 100. In order to allow thedistal tip 32 of the driver 30 to fit within and engage the inner lumen100 c of the suture anchor 100, the opposed ends of the suture 36extending from the suture-engaging member 14 can be seated within theopposed grooves (only one groove 34 a is shown) formed in the tip 32.

In another embodiment, as shown in FIGS. 4A and 4B, the driver 40 can becannulated to allow the terminal ends of a suture(s) extending throughthe suture anchor to extend therethrough, rather than extending externalto the driver. In particular, the driver 40 is similar to driver 30,except that the driver 40 includes an inner lumen 40 c extending throughthe entire length thereof for receiving one or more sutures, rather thanhaving suture-receiving grooves formed in the distal tip. FIG. 4Aillustrates the distal tip 42 of the driver 40 disposed within andengaging the inner lumen 10 c of suture anchor 10. As shown, thediameter of the remainder of the driver 40 as compared to thereduced-diameter of the distal tip 42 can provide a stop surface 44 thatlimits the depth of insertion of the distal tip 42 into the inner lumen10 c of the anchor 10. As previously discussed, the length of the distaltip 42, and thus the depth of insertion of the tip 42 into the innerlumen 10 c of the anchor 10, can vary depending on the size and shape ofthe suture anchor 10. In an exemplary embodiment, the tip 42 isconfigured to be inserted into a substantial portion of the inner lumen10 c so as to maximum surface contact between the driver 40 and thesuture anchor 10. In other embodiments, the cannulated driver 40 canalso optionally be used to allow other materials, such as bone-growthpromoting materials, adhesives, biologics, and other injectablematerials, to be introduced through the driver and into the sutureanchor.

As previously indicated, the suture anchors and drivers disclosed hereincan be configured for use with one or more sutures. The particularquantity of sutures used with a suture anchor and driver can depend onthe size of the suture anchor and the driver, and in particular on thediameter of the inner lumen of the suture anchor and the size of thesuture-engaging groove formed in the driver (for driver 30) or thediameter of the lumen in the driver (for driver 40). For example, wherethe suture anchor has a relatively small inner lumen, the driver willnecessarily have a relatively small diameter and thus smallsuture-engaging grooves (for driver 30) or a small inner lumen (fordriver 40). It may therefore only be possible to use a single suturethat is positioned around the suture-engaging member on the sutureanchor, and that has two trailing ends extending through thesuture-receiving grooves in the driver (for driver 30) or through theinner lumen in the driver (for driver 40). While a single suture can besufficient to anchor tissue to bone, it is preferred to use more thanone, and more preferably two, sutures. Thus, rather than increasing asize of the suture anchor and/or the driver, the present inventionprovides various exemplary techniques for utilizing two sutures with asuture anchor and driver that are configured to seat only one suture.This is particularly advantageous as the suture anchor can be sized tobe fully disposed within cortical bone, while the diameter of the innerlumen of the suture anchor and of the distal tip of the driver aremaximized to increase the torque failure rating. This also enables theanchor to be made from a broad range of materials, including brittle orweaker materials such as those previously disclosed herein.

In one embodiment, one or more sutures can be coupled to a thin wire,thread, string, small diameter suture, etc. (hereinafter genericallyreferred to as a wire), and the wire can extend through thesuture-receiving grooves or inner lumen in the driver. Since the wirewill have a diameter that is significantly smaller than a diameter ofthe suture, one or more wires can be used in place of the trailing endof one or mores sutures, thus allowing multiple sutures to be used. Thisis illustrated, by way of non-limiting example, in FIGS. 5A and 5B.

FIG. 5A illustrates a suture anchor 10 having first and second sutures16, 18 extending therethrough and around the suture-engaging member (notshown). Since all four trailing ends (i.e., the ends extending from thesuture-engaging member) of the sutures 16, 18 will not fit within thesuture-receiving grooves in driver 30 (not shown) or through the innerlumen of driver 40 (not shown), only one trailing end of each suture 16,18 can extend through the driver and the terminal end 16 b, 18 b of theother trailing end of each suture 16, 18 can be positioned just distalto the proximal end of the cut-out 22. A wire 50 can be mated to eachterminal end 16 b, 18 b and the wire can extend proximally from theterminal ends 16 b, 18 b and through the driver. In use, once the sutureanchor 10 is implanted in bone, the driver can be removed and the wire50 can be pulled to pull the terminal ends 16 b, 18 b of the sutures 16,18 proximally around the suture-engaging member and through the sutureanchor 10. The terminal ends can thereafter be used to secure tissue tobone. A person skilled in the art will appreciate that the sutures canremain external to the driver and anchor while only the wire(s) extendthrough the driver and anchor, and the sutures can be pulled into theanchor after placement of the suture anchor.

In another embodiment, shown in FIG. 5B, the terminal ends 16 b, 18 b ofthe sutures 16, 18 can be mated to separate wires 52, 54 that extendthrough the inner lumen of the driver. FIG. 5B illustrates a partiallycut-away view of the suture anchor 10, showing the distal tip 42 ofdriver 40 disposed therein and having the wires 52, 54 extendingtherethrough. As with the embodiment shown in FIG. 5A, one trailing endof each suture 16, 18 and the wires 52, 54 can extend through the driver40, thus allowing two sutures 16, 18 to be used with the anchor 10.After the suture anchor is implanted, the driver 40 can be removed andthe wires 52, 54 can be used to pull the terminal ends 16 b, 18 b of thesutures 16, 18 around the suture-engaging member in a proximaldirection, as shown in FIG. 5C. A person skilled in the art willappreciate that while FIG. 5B illustrates driver 40, the wires can beused with driver 30, or with any other driver known in the art.

The use of wires extending through a cannulated driver can also beadvantageous in that various materials, such as those previouslydiscussed, can be introduced through the inner lumen of the driver withthe wires in place. For example, an adhesive can be injected through theinner lumen of the driver prior to pulling the terminal ends 16 b, 18 bof the sutures 16, 18 proximally, thus allowing the suture 16, 18 to besecured to the suture anchor 10.

A person skilled in the art will appreciate that a variety of techniquescan be used to mate a wire to one or more sutures. By way ofnon-limiting example, FIGS. 6-10 illustrate various exemplary matingtechniques. In the embodiment shown in FIG. 6, a single wire 60 isthreaded through a terminal end 62 a of a first suture 62 and then isthreaded back through a terminal end 64 a of a second suture 64 suchthat trailing ends 60 a, 60 b of the wire 60 extend from the terminalends 62 a, 64 a of the sutures 62, 64. In another embodiment, shown inFIG. 7, the wire 70 is looped or knotted around the terminal ends 72 a,74 a of two sutures 72, 74 such that trailing ends 70 a, 70 b of thewire 70 extend from the terminal ends 72 a, 74 a of the sutures 72, 74.In the embodiment shown in FIG. 8, the wire 80 is positioned between twosutures 82, 84 and it is welded to the sutures 82, 84 using anultrasonic welder 86, or using other welding techniques known in theart. In another embodiment, shown in FIG. 9, a wire 90 can be attachedto a clamp or crimp band 96 that is disposed around and closed to engagethe terminal ends 92 a, 94 a of two sutures 92, 94. In yet anotherembodiment, shown in FIG. 10, the wire 110 can include a spring orcoiled portion 110 c formed on a terminal end thereof. The coiledportion 110 c can be positioned around the terminal end 112 a of asuture 112, and it can be biased to a shape in which the coiled portion110 c engages the suture 112. When the wire 110 is pulled to pull thesuture 112, the coiled portion 110 c can optionally decrease in diameterto provide a more secure engagement between the wire 110 and the suture112. A person skilled in the art will appreciate that the aforementionedmating techniques can be used to mate a single wire to one or moresutures, or to mate multiple wires to a single suture. Moreover, avariety of other mating techniques can be used, including adhesives etc.

In another embodiment, one of the trailing ends of a suture or a wirecan be mated to the driver. As the driver is removed from the sutureanchor, the driver will pull the suture or wire attached thereto aroundthe suture engaging member. This is illustrated in FIGS. 11A and 11B. Inthe embodiment shown in FIG. 11A, a first end 132 a of a wire 132 isattached to a distal end 130 d of a driver 130. The second end 132 b ofthe wire 132 extends through the suture anchor 10 and proximally fromthe driver 130, where it can be coupled to a suture. The wire 132 can bepulled into the suture anchor 10 and around the suture-engaging member14 as the driver 130 is removed. In another embodiment shown in FIG.11B, the first end 132 a′ of the wire 132′ can be attached to a proximalend 130 p′ of the driver 130′. A person skilled in the art willappreciate that the particular attachment location of the wire to thedriver can vary. Moreover, a variety of techniques can be used to attacha suture or a wire to a driver. By way of non-limiting example, FIG. 11Cillustrates one exemplary embodiment of an attachment technique. Asshown, the distal tip 152 of a driver includes first and second bores152 a, 152 b formed therein, and the trailing ends of first and secondwires 154, 156 are inserted through the bores 152 a, 152 b. A knot isformed in the terminal end of each wire 154, 156 to retain the wires154, 156 within the bores 152 a, 152 b. In use, instead of having fourtrailing ends of two sutures extending through the driver, only onetrailing end of each suture or wire will extend through the driver whilethe other end will remain attached to the distal tip 152. Alternatively,the trailing ends of two wires can extend through the driver and attachto sutures positioned external to the driver. When the driver isremoved, the driver will pull the sutures around the suture-engagingmember to allow the trailing ends of the sutures to be used to securetissue to bone. The knots can be cut or otherwise removed to detach thesutures from the driver.

In other embodiments, shown in FIGS. 12A-12D, various threadingtechniques can be used to allow two sutures to be used with the sutureanchors disclosed herein. FIG. 12A illustrates suture anchor 10 havingtwo sutures 16, 18 extending through the inner lumen 10 c of the sutureanchor 10 and looped around the suture-engaging member 14. Conversely,one of the sutures, e.g., suture 18, can extend along an externalsurface of the suture anchor 10, as shown in FIG. 12B. Similarly, asingle suture can be used and it can extend through both the inner lumen10 c of the suture anchor 10, as well as along an external surface ofthe suture anchor 10. This is illustrated in FIG. 12C. As shown, a firsttrailing end 16 a of the suture 16 is positioned along an externalsurface of the suture anchor 10, and the second trailing end 16 b of thesuture 16 is threaded around the suture-engaging member 14 and upthrough the inner lumen 10 c, where a first loop is formed. The secondtrailing end 16 b of the suture 16 is then passed back through the innerlumen 10 c and positioned to extend externally along the length of thesuture anchor 10. While FIG. 12C illustrates both trailing ends 16 a, 16b of the suture 16 extending externally along the suture anchor 10, inanother embodiment one trailing end can extend externally along thesuture anchor 10 while the other trailing end can extend through theinner lumen 10 c of the suture anchor 10. This is illustrated in FIG.12D, which shows the suture 16 having a first trailing end 16 aextending through the inner lumen 10 c of the suture anchor 10 andproximally beyond the proximal end 10 a of the suture anchor 10. Thesecond trailing end 16 b is passed through the inner lumen 10, aroundthe suture-engaging member 14, and externally around the suture anchor10. It is then passed back into the proximal end 10 a of the sutureanchor and through the inner lumen 10 c, where it is positioned aroundthe suture-engaging member 14 and externally along the suture anchor 10.A person skilled in the art will appreciate that a variety of otherthreading techniques can be used to allow one or more sutures to be usedwith the various suture anchors and/or drivers disclosed herein.

The present invention also provides exemplary methods for anchoringtissue to bone. While the method is described in connection withattaching soft tissue to bone, the methods and devices disclosed hereincan be used in a variety of medical procedures for anchoring onestructure to another. In general, a bore is formed in bone of a patient.The diameter of the bore is preferably slightly less than the largestouter diameter of the suture anchor, and the length of the bore itpreferably the same as or slightly greater than a length of the sutureanchor. The bore will extend fully through the cortical bone to allowthe suture anchor to be fully engaged through the thickness of thecortical bone. The bore can also extend into the cancellous bonedepending on the length of the suture anchor. One or more sutures(including sutures with wires coupled thereto) can be coupled to thesuture anchor using various techniques, as previously discussed herein,and the distal tip of a driver can be inserted into the lumen in thesuture anchor. The trailing ends of the suture(s) or wire(s) can extendexternally along the driver or they can extend through an inner lumen ofthe driver. The driver can then be used to insert the suture anchor intothe bone tunnel. For example, where the suture anchor includes threadsformed thereon, the driver can be rotated to thread the suture anchorinto the bone hole. The threads will engage the bone hole therebypreventing removal of the suture anchor. In other embodiments, thedriver can be used to tap the bone anchor into the bone hole, and aninterference fit, compression fit, and/or surface features, such as ribsor protrusions, formed on the suture anchor can be used to retain thesuture anchor within the bone hole. The driver can also optionally beused to impact a threaded suture anchor into the bone hole. The threadscan allow for later removal of the suture anchor.

Once the bone anchor is properly anchored within the bone hole, variousmaterials, such as those previously discussed herein, can be introducedthrough the driver and into or around the suture anchor. The driver canthen be removed. Where the suture(s) have wire(s) attached thereto, thewire(s) can be pulled to pull the suture(s) around the suture-engagingmember of the suture anchor. If the suture anchor includes a rotatablesuture-engaging member, the suture-engaging member will rotate as thesuture(s) is pulled therearound. The trailing ends of the suture(s) canthen be used to anchor soft tissue to the bone. For example, one or bothtrailing ends of the suture(s) can be attached to a needle to allow theneedle to be used to thread the suture through tissue to be anchor tothe bone. The suture(s) can be threaded through tissue either prior toor after insertion of the suture anchor into bone. Once the soft tissueis approximated toward the bone, the trailing ends of the suture(s) canbe secured together and the excess trimmed as is typical in thesesituations to complete the surgery.

One skilled in the art will appreciate further features and advantagesof the invention based on the above-described embodiments. Accordingly,the invention is not to be limited by what has been particularly shownand described, except as indicated by the appended claims. Allpublications and references cited herein are expressly incorporatedherein by reference in their entirety.

What is claimed is:
 1. An apparatus for anchoring tissue to bone,comprising: a suture anchor that includes at least one surface featureadapted to engage bone and formed on an external surface thereof alongless than an entire longitudinal length of the suture anchor, thatincludes an inner lumen extending therethrough between proximal anddistal ends of the suture anchor, that has opposed cut-outs formed in asidewall thereof and extending proximally from a distal-most endthereof, and that includes a rotatable member extending across opposedsidewalls of the inner lumen in a distal portion of the suture anchorsuch that a suture can extend around the rotatable member and trailingends of the suture can extend through the inner lumen of the sutureanchor, the rotatable member being located distal to proximal ends ofthe opposed cut outs; and a driver having an elongate shaft and a distalend adapted to be advanced distally into a proximal end of the innerlumen so as to engage a proximal portion of the inner lumen of thesuture anchor such that after the distal end of the driver has beenadvanced distally into the proximal end of the inner lumen and thedistal end of the driver is engaging the proximal portion of the innerlumen, the driver is adapted to rotate so as to rotate the suture anchorsuch that the at least one surface feature penetrates into the bone. 2.The apparatus of claim 1, wherein the elongate shaft includes an innerlumen extending therethrough for receiving the suture extending throughthe inner lumen of the suture anchor.
 3. The apparatus of claim 1,wherein the distal end of the elongate shaft includes opposed cut-outsformed therein for allowing the suture extending from the suture anchorto extend externally along the elongate shaft of the driver.
 4. Theapparatus of claim 1, wherein the distal end of the elongate shaft hasan asymmetrical cross-sectional shape, and wherein at least the proximalportion of the inner lumen the suture anchor has a complementaryasymmetrical cross-sectional shape.
 5. The apparatus of claim 1, whereinthe rotatable member comprises a pin extending between the opposedsidewalls of the inner lumen of the suture anchor.
 6. The apparatus ofclaim 1, wherein the rotatable member is positioned adjacent to thedistal end of the suture anchor.
 7. The apparatus of claim 1, whereinthe rotatable member is non-removably disposed in the distal portion ofthe inner lumen of the suture anchor.
 8. The apparatus of claim 1,wherein the inner lumen defines a longitudinal axis, and the rotatablemember extends across the opposed sidewalls at a fixed axial positionalong the longitudinal axis.
 9. The apparatus of claim 1, wherein atleast one of the driver and the suture anchor includes a stop mechanismadapted to prevent the distal end of the driver from extending distallybeyond a proximal end of the rotatable member after the distal end hasbeen advanced distally into the proximal end of the inner lumen and thedistal end of the driver is engaging the proximal portion of the innerlumen.
 10. The apparatus of claim 1, wherein the at least one surfacefeature extends from the proximal end of the suture anchor andterminates proximal to the rotatable member.
 11. The apparatus of claim1, wherein the at least one surface feature comprises at least onethread formed on and extending around the external surface of the sutureanchor.
 12. The apparatus of claim 11, wherein the at least one threadextends from the proximal end of the suture anchor and terminatesproximal to the rotatable member.
 13. The apparatus of claim 1, whereinthe at least one surface feature comprises at least one of one or moreridges formed on and extending around the external surface of the sutureanchor and one or more protrusions extending radially outward from theexternal surface of the suture anchor.
 14. The apparatus of claim 1,wherein, when the suture extends around the rotatable member, thetrailing ends of the suture extend through the inner lumen and exit thesuture anchor through the proximal end of the inner lumen, and thetrailing ends of the suture extend through an inner lumen formed in thedistal end of the driver.
 15. The apparatus of claim 1, wherein therotation of the driver advances the distal portion of the suture anchorinto a hole in the bone without the external surface of the sutureanchor in the distal portion thereof penetrating into sidewalls of thehole in the bone.
 16. The apparatus of claim 1, wherein the opposedsidewalls define opposed arms at the distal end of the suture anchor,the rotatable member being positioned between the opposed arms.
 17. Anapparatus for anchoring tissue to bone, comprising: a cannulated sutureanchor having at least one thread formed thereon, an inner lumenextending through the suture anchor between proximal and distal ends ofthe suture anchor, and a rotatable member extending across opposedsidewalls of the inner lumen such that a suture can extend around therotatable member and trailing ends of the suture can extend through theinner lumen of the suture anchor and out the proximal end of the sutureanchor, the thread extending around an external surface of the sutureanchor and being configured to penetrate into bone, and the rotatablemember extending across the opposed sidewalls in a distal portion of thesuture anchor at a fixed axial position along a longitudinal axis of theinner lumen; and a driver having an elongate shaft and a distal endconfigured to be advanced into the proximal end of the suture anchor soas to engage a proximal portion of the inner lumen of the suture anchor,with the trailing ends of the suture extending through the inner lumenof the suture anchor and out the proximal end of the suture anchor, suchthat rotation of the driver rotates the suture anchor relative to thebone to drive the suture anchor into the bone with the at least onethread threadably engaging the bone.
 18. The apparatus of claim 17,wherein the at least one thread extends from the proximal end of thesuture anchor and terminates proximal to the rotatable member.
 19. Theapparatus of claim 17, wherein the at least one thread is locatedentirely proximal to the rotatable member.
 20. The apparatus of claim17, wherein the rotation of the driver advances the distal portion ofthe suture anchor into the bone without the external surface of thesuture anchor in the distal portion thereof threadably engaging thebone.
 21. The apparatus of claim 17, wherein the at least one threadextends around the external surface of the suture anchor in a proximalportion of the suture anchor and terminates proximal to the distalportion of the suture anchor, and the rotatable member is exposedthrough the opposed sidewalls to an outside environment.
 22. Theapparatus of claim 17, wherein the suture anchor includes a unitaryelongate body having the inner lumen extending therethrough, the opposedsidewalls in the distal portion of the suture anchor being defined byopposed surfaces of the elongate body, and the rotatable member beingattached to the opposed surfaces of elongate body in the distal portionof the suture anchor.
 23. An apparatus for anchoring tissue to bone,comprising: a suture anchor having at least one thread adapted to engagebone and formed on an external surface thereof along less than an entirelongitudinal length of the suture anchor such that the suture anchor hasa threaded proximal portion including the at least one thread and has anunthreaded distal portion, an inner lumen extending through the sutureanchor between proximal and distal ends thereof, an opening formedthrough a sidewall thereof and fully contained in the distal portionthereof, and a rotatable member extending across opposed sidewalls ofthe inner lumen such that a suture can extend around the rotatablemember and trailing ends of the suture can extend through the innerlumen of the suture anchor, the rotatable member being fully containedin the unthreaded distal portion of the suture anchor, the rotatablemember being exposed through the opening, and the rotatable member beingconfigured to rotate 360°; and a driver having an elongate shaft and adistal end adapted to be advanced distally into a proximal end of theinner lumen so as to engage a proximal portion of the inner lumen of thesuture anchor and rotate, thereby causing rotation of the suture anchorsuch that the at least thread penetrates into the bone.